The unusually high occurrence of hematological abnormalities in pediatric-SLE in Saudi children - possible causes and diagnostic significance

Abstract

Listen

Translate article

Systemic Lupus Erythematosus (SLE) is an autoimmune disease with a highly variable and complex symptomatology. Indeed many clinicians working with SLE regard it as a group of diseases [1]. In SLE, autoantibodies are formed against DNA, protein and phospholipid antigens leading to the generation of inflammation and damage in many types of tissue including skin, joints, kidneys, lungs and the nervous system. Depending on the clinical presentation, an SLE patient may be referred to a dermatologist, rheumatologist, hematologist, nephrologist, neurologist or psychiatrist [1], receiving different treatment from each specialist. To complicate matters further, SLE is characterized by periods of well-being interspersed with disease flares. The prognosis had improved greatly in the last 60 years. In the early 1950s, the 5 years survival rate for SLE was 50%, but now it is higher than 90% [2]. This dramatic improvement is due to physicians’ diagnostic skills and to the early administration of immunosuppressive drugs, typically corticosteroids, hydroxychloroquine, methotrexate or more recently, Rituximab, a chimeric monoclonal antibody directed against CD20 on the B-cell surface. Prompt diagnosis is crucial to patient prognosis, especially maintenance of renal function [3]. However, SLE presents with such a variety of symptoms that diagnosis is not at all straightforward. In this issue of The Journal of Pediatric Biochemistry, Mohammed Muzaffer reports hematological data from a study of Saudi Arabian children with SLE (pediatric SLE). A remarkable finding of this study is that hematological abnormalities were present in 83% (30 of 36 children) of pediatric SLE (p-SLE) children. As Muzaffer points out, this occurrence is much higher than other studies have found in p-SLE in the USA, France and the Middle East, including Saudi Arabia and Kuwait. A recent study in Kuwait [4] found that only 20% of children were anemic, whereas Muzaffer’s study in Jeddah, Saudi Arabia, finds anemia in 80% of his group. Clearly this large difference in the clinical presentation of p-SLE in two geographically juxtaposed and ethnically related countries may indicate something important about pediatric SLE etiology. Genome wide association studies have confirmed more than 20 robust associations of loci in the human genome with susceptibility to SLE [5] and estimates put the total number of SLE-associated genes at as much as 100. Curiously, the genetic architecture of SLE has more in common with Crohn’s disease, which also has